A wide variety of techniques have been developed to prepare and analyze biological samples for analysis. Biological samples, e.g., tissue sections or cells, can be mounted on microscope slides for diagnostic purposes. The biological samples are often treated with one or more substances (e.g., dyes, reagents, etc.) to add color and contrast to otherwise transparent or invisible cells or cell components. The treated biological samples are often covered with coverslips to avoid contamination of the biological samples and to permit long-term archiving of the slides.
Automated coverslippers can be used to automatically place glass coverslips on specimen-bearing microscope sides. For example, automated coverslippers often pick up a coverslip from a stack of coverslips and place the coverslip onto a specimen-bearing slide. Unfortunately, automated coverslippers can pick up more than one coverslip because coverslips frequently stick together due to static forces, vander waal forces, or moisture between adjacent coverslips. This may result in two or more coverslips being mounted on a slide. It may be difficult to remove the excess coverslip(s) from the slide. If the automated coverslipper attempts to transport stuck-together slides, coverslips may drop resulting in loose coverslips in automated processing equipment. The loose coverslips can result in damage and/or malfunction of the automated processing equipment and may result in “downtime” for maintenance. Unfortunately, automated coverslippers are not capable of accurately counting coverslips during handling.
Overview of Technology
At least some embodiments of the technology are directed to a system for detecting substrates. The system is capable of differentiating between zero, one, or multiple substrates in a stack. The system can detect substrates in the form of, for example, coverslips (e.g., coverslips for microscope slides), screens (e.g., transparent screens for computing devices, smartphones, tablets, or the like), protective sheets, or other items through which electromagnetic radiation is capable of traveling. The substrates can be transparent or semi-transparent.
In some embodiments, a system for detecting substrates includes an optically anti-reflective element and an optical sensor. The optical sensor includes a light source and a light detector. The light source is positioned to output light towards the optically anti-reflective element. The light detector is positioned to detect the light reflected by one or more substrates located between the light detector and the optically anti-reflective element. Information about the substrates can be determined based on the reflected light. The information can include, for example, the presence of substrates, the number of substrates, optical properties of the substrates, or the like. For example, the reflected light can be used to count the number of substrates in a stack of substrates.
The optically anti-reflective element, in some embodiments, can absorb incident or impinging light to manage noise (e.g., optical noise). The noise can be, for example, light reflected from surfaces adjacent to the substrates. In some embodiments, the optically anti-reflective element can be positioned to limit, reduce, or substantially eliminate noise caused by such reflected light. The reflected light (i.e., the signal from the substrates) received by the light detector can thus be used to accurately detect the substrates.
In some embodiments, a substrate analyzer can include an optical sensor and an optical element. A holder mechanism can carry one or more substrates to a detection zone between the sensor and optical element. The substrate analyzer can evaluate the detection zone to count the number of substrates, if any, within the detection zone. The optical sensor can be carried by, or part of, the holder mechanism such that the optical sensor is properly positioned with respect to the substrate. In some embodiments, the optical sensor and optical element are stationary. The holder mechanism can carry substrates into the detection zone. In other embodiments, the optical sensor can be stationary and the optical element is part of the holder mechanism.
In some embodiments, a detector comprises an optical element and an optical sensor. In one embodiment, the optical element is a noise-reducing element that inhibits, limits, or substantially prevents the reflection of light that has traveled through a stack of substrates. The noise-reducing element can include, without limitation, one or more optically anti-reflective elements with low-remission surfaces, light-absorbing characteristics, or the like.
In some embodiments, a slide processing apparatus includes a processing station configured to process a specimen on a microscope slide and a coverslipper. The coverslipper receives and applies coverslips to microscope slides processed by the processing station. The coverslipper can include one or more coverslip detectors used to detect coverslips. A coverslip detector, in some embodiments, includes an optically anti-reflective element and an optical sensor. The optical sensor is positioned to deliver light along a path towards the anti-reflective element and to detect light reflected by any coverslips positioned along the path. In some embodiments, the coverslip detectors can include an array of light sensors and detectors to simultaneously analyze multiple coverslips.
In one embodiment, a detection method comprises delivering light towards a coverslip such that a portion of the light is reflected by the coverslip and a portion of the light travels through the coverslip and strikes an optically anti-reflective element. The light reflected by the coverslip can be detected to, for example, determine a presence or a number of coverslips. In one embodiment, the coverslip is held against the optically anti-reflective element while detecting the reflected light. For example, the coverslip can cover the optically anti-reflective element.
In some embodiments, a method of detecting substrates includes carrying at least one substrate to a detection zone using a holder mechanism. The detection zone can be located between a light detector and an optically anti-reflective element. Light is delivered towards the optically anti-reflective element such that a portion of the light is reflected by the substrate and a portion of the light, which travels through the substrate, strikes the optically anti-reflective element. The light reflected by the substrate can be detected, and a number of substrates at the detection zone can be determined based on the detected light.
A delivery location of the substrates can be determined based, at least in part, on the presence or number of substrates. A controller, in some embodiments, can determine the delivery location based on the number of detected substrates. In some embodiments, the controller can command the holder mechanism to move the substrates to a first location if one substrate is detected and a second location a plurality of substrates are detected.